Parallel support element for workpieces



N. s. LIEPTZ Nov. 26, 1963 PARALLEL SUPPORT ELEMENT FOR WORKPIECES Filed July 24, 1961 Fig.6 Fi 8 Fi /0 Fig.5

INVENTOR.

NATHAN S. LIEPTZ BY g Q X i x l i li, I

ATTORNEYS United States Patent 3,112,106 PARALLEL SUllORT ELEMENT FOR WORKPIECES "Nathan S. Lieptz, 23506 Beachwood Blvd, Beachwood 21, Ohio Filed July 24, 1961, Ser. No. 126,009 8 Claims. (Cl. 269-496) The invention relates, in general, to gauge elements or devices of the type generally referred to as parallel blocks or parallels, which are customarily used in pairs as precision supporting surfaces for a workpiece which is to be machined, inspected or otherwise subjected to usual machine shop practices.

The rectangular blocks or parallels are provided with opposite1y-disposed, precision-ground, parallel surfaces. The blocks are placed upon a plane surface, such as the table of a machine tool or a surface plate, and are intended to support a workpiece at an elevated position in parallelism with the plane surface. The blocks are made in various standard increments of height such as A", /2, A", l", 1%", etc., and come in various lengths, for example, 4", 6", etc. The thickness or width of a block usually increases proportionately as its size or height is increased, as it is considered necessary to utilize a substantial mass of metal to avoid warpage or other deformations that might result from climatic conditions or from use. A width of /4 is generally the minimum practicable width for the smaller size blocks. Blocks which are 1" or more in height, usually have a minimum width of /2 and this is increased to A2", 4", etc., as the height is increased.

The parallel blocks are generally used in association with an adjustable vise or other clamping means for retaining the work piece in the desired position on a machine tool table or the like.

The conventional parallel blocks, above described are expensive, are relatively heavy, occupy considerable space in the machinists tool box, must be very carefully handled to avoid injury or distortion, and cannot be conveniently utilized for the support of very narrow workpieces.

It is the primary object of my invention to provide an element, for use as a parallel support, which is particularly adaptable for use in the vise-clamping of narrow workpieces.

Another object of my invention is to provide an element, for use as a parallel support, which is light in weight and occupies relatively little space, yet provides a large effective support area for a workpiece.

A further object of my invention is to provide an improved parallel support element which is far less costly than the conventional parallel blocks presently in use.

Still another object of my invention is to provide an element of the character described which is adapted for multiple uses in a machine shop.

Other objects and advantages of my invention will be apparent during the course of the following description.

In the accompanying drawings forming a part of this specification and in which like numerals are employed to designate like parts throughout the same,

FIG. 1 is fragmentary view in elevation of a narrow workpiece supported on a parallel element embodying the features of my invention.

FIG. 2 is a fragmentary cross-sectional view taken on line 2-2 of FIG. 1.

FIG. 3 is a cross-sectional View taken on line 3-3 of FIG. 2.

FIG. 4'is a view similar to FIG. 2, but showing a pair of my parallel elements utilized for supporting a wide workpiece.

FIG. '5 is a view similar to FIG. 2, but showing a manice ner of utilizing the parallel element for another purpose.

FIG. 6 is a view similar to FIG. 5 and showing the manner of utilizing the parallel element as a hold-down device.

FIG. 7 is a view similar to FIG. 5 showing the manner of utilizing the parallel element as an improved V block.

FIGS. 8 and 9 are fragmentary plan views which each show modified forms of the configuration of a parallel element embodying the features of my invention.

FIGS. 10 and 11 are fragmentary plan views which each show other modifications which may be made in the form of a parallel element embodying the features of my invention.

Referring more particularly to FIGS. 1-3 of the drawings, I have diagrammatically indicated a table 15 of a milling machine or the like on which a narrow rectangular workpiece 16 is supported for a machining operation on its upper end surface 17. The workpiece 16 has a plane lower end surface 18 opposite the surface 17.

A suitable vise 19, having a fixed jaw 20 and a screwoperated movable jaw 21, is secured by suitable means to the table 15. The vise 19 is representative of any known clamping means which may be utilized for retaining the workpiece in a selected position above the table 15. The surface 1 8 of the workpiece 16 rests upon a parallel element 22 having parallel, precision-ground opposed edges or surfaces 23. The workpiece rests upon the upper edge 23, and the lower edge 23 of the element 22 rests upon a plane base member 24 of the vise 19. The workpiece is thus elevated to such convenient or desirable height above the table 15 as may be required for the machining operation which is to be performed. By means of the vise 19, it is clamped in this position, and by means of theparallel element 22, the surface 18 of the workpiece is positioned in a fixed reference plane with respect to the surface of the table 15.

The height of the parallel element 22 may be of any suitable dimension, it being understood'that the machinist will ordinarily be provided with a set of elements 22 of different heights to accommodate a variety of work arrangements which may be encountered. The term height, as used herein with reference to the parallel element 22, is the linear dimension between the opposite ground surfaces 23; The elements may, for example, be provided in suit-able increments of height to provide a range from A2 to 6". The element is rig-id in the direction of its height, but is preferably resiliently compressible in the direction of its effective support width, as described hereinafter.

As best seen'in FIGS. 2 and 3, the parallel element 22 is a formed or bent piece of thin metal, or the like, having a lateral wave-like configuration or corrugation, in its direction of rigidity, which is preferably of uniform pitch and likewise of uniform depth or amplitude. The thickness of the parallel element 22 will ordinarily be within the range of sheet metal gauges or in the range of about .005 to .125 inch, depending somewhat on the character of the material which is used; The'length of element 22 can be any practicable length which is required. Thus, for example, the length could be in the range from 1" to 36".

The element 22 will, in most instances, be made of spring annealed temper steel or similar metal which, by suitabletreatment or otherwise, is characterized by a relatively high value of resiliency so'that it will not take a permanent set when subjected to deformation during its utilization. For example, in lieu of steel, a spring Phosphor-bronze metal may be desirable under certain circumstances; or, where conditions made it desirable, a hard and durable element 22- of resilient synthetic resin may be utilized. When steel is utilized for the element 3 22, I have found that a metal thickness of from .010 to .025 inch is satisfactory and suitable for most purposes. Where a non-metal such as synthetic resin is used, the thickness required will ordinarily be relatively greater.

In FIG. 2, I have shown, in solid lines, the element 22 clamped and compressed between the clamping jaws and 21, as the jaws have been moved to clamping engagement with the narrow workpiece 16. It will be noted that, as shown in phantom outline, the amplitude or effective support width of the unstressed element 22 is initially greater than the width of the workpiece 16. Were the element 22 a conventional form of parallel block, it would not be possible to clamp the workpiece directly between the vise jaws, as the width of the conventional parallel would cause it to be clamped before the workpiece. Therefore, under such circumstances, the machinist would have to find inserts of some suitable character which could be interposed between the workpiece and the clamping jaws in order to clamp the narrow workpiece. By means of the disclosed element 22, however, the use of such expedients is made unnecessary. As the clamping jaws are tightened, the resilient element 22 is compressed and a temporary deformation occurs to reduce its amplitude to the point at which the clamping jaws engage the workpiece 16. This temporary decrease in effective width is translated into increased length of the element 22. Thus an element 22 whose amplitude or effective support width in the unstressed condition is greater than the width of the workpiece is readily utilized for such a narrow workpiece. For example, an element 22 whose effective support width is .750" can be compressed to an elfective width which corresponds substantially to the thickness of the element 22, for example, .020". It can thereby serve as a parallel support for clamped workpieces whose width is well under A as well as providing a /1" support width in the unstressed condition, for workpieces which are wider than M".

From the foregoing it is apparent that a parallel element, in accordance with my invention, is usable over a very wide range of workpiece widths, and is particularly adaptable to the support of very narrow workpieces. Thus, only one size of my element 22 can serve in lieu of several sizes of conventional parallel blocks which might be needed to accommodate an equivalent range of workpiece variations.

The resiliency of the element 22 is such that it will not adopt a permanent set in response to the compression, as above described, but will return to its unstressed initial configuration when the compressive forces are released. It is of interest to note that the resiliency of the element 22 also aids in the manipulation of the clamping vise 19. Such screw-type vises, after a period of use, have sufficient screw wear to permit considerable play. As a consequence, the movable jaw 21 of the vise will not respond immediately to a reverse rotation of the screw such as might be required to make some minor adjustment in the position of the clamped workpiece. However, the resiliency of the element 22, causes the jaw 21 to respond immediately to opening movement of the screw and thus eliminates this minor but aggravating and time consuming problem of play in the clamping device.

In FIG. 4, I have shown a pair of unstressed elements 22 which are utilized under a workpiece which is relatively wider than the workpiece 16. Again assuming that the effective width of each element 22 is it can be seen that the pair of elements would provide two spaced support areas, each having an effective width of for a workpiece 25 which might, for example, be 2" wide. However, if the workpiece 25 were, for example, only 1%" wide, two conventional parallel blocks, each /4 wide could not be used. In contrast, as indicated in phantom outline in FIG. 4, one of the pair of elements could be shifted in position so that the pair of elements 22 would provide a combined effective support width which is less than the sum of their individual effective support widths. The arrangement thus provides a modulation ability in the positioning of the unstressed elements 22 to provide a maximum support area for a wide variety of dimensional conditions. This nesting adaptability of a plurality of elements 22 also serves as a spacesaving means in the storage of the elements in the machinists tool box, or the like. For example, approximately nineteen pairs of elements 22 having a thickness of .020" and an amplitude of /1" would occupy the same storage space as only one pair of conventional parallel blocks having a thickness of A". The weight of a pair of steel elements 22 would similarly approximate only A of the weight of an equivalent pair of conventional parallel blocks.

These savings in material, plus other manufacturing advantages, such as using narrow pre-sized coils of spring steel which lend themselves to continuous mass-production manufacturing techniques, can be translated into manufacturing economies whereby a pair of elements 22 can be manufactured for less than 20% of the cost of an equivalent pair of conventional parallels.

It may also be noted at this time, that the ground surfaces of conventional parallels, after a period of use, hecome dirty, oil encrusted, and otherwise contaminated and inaccurate, so as to be unusable without a careful and thorough cleaning. This undesirable consequence is substantially minimized or obviated in the elements 22 because the actual area of the ground surfaces 23 is only a small fraction of the effective support width of the element. The ground surface 23, being almost an edge rather than a surface, is less susceptible to retaining foreign matter than the comparable conventional parallel block and therefore will not permit accumulation of such matter to the same degree as the larger conventional parallel.

The relatively small actual contact area of the element 22 also has the advantage of a greater degree of accuracy as it will ordinarily slip off any small projections on the workpiece surface which are out of the parallel plane. Alternatively, the element 22 is easily shifted slightly to avoid any rough spot on the workpiece. Ordinarily, the conventional parallel blocks would not lend themselves, at least as conveniently, to such a procedure.

In FIGS. 5, 6 and 7, I have shown some other ancillary uses to which the element 22 may be put by the machinist. In FIG. 5, the element 22, on the left side of the figure, is shown being used as a resilient spacer between a thin workpiece 26 and one of the clamping jaws of the vise 19. Under circumstances where the workpiece is thin, soft, fragile or otherwise must be delicately handled in the clamping operation, the element 22 can, when used in this manner, act as a yieldable buffer between the workpiece and the clamping jaw so that the workpiece is not subjected to the direct pressure of the clamp, but, instead can be clamped by the adjustable and more delicate spring pressure of the element 22.

The other element 22, shown in FIG. 5, is utilized as a resilient support under the clamped workpiece 26. This arrangement can be utilized when, for some reason, it is not desirable that the workpiece be in a parallel position but that it be at a slight angle to the machine tool table 15. Under these circumstances, the position of the workpiece is established by the use of gauging devices, but the workpiece may have to be clamped and reclamped several times to make minor positional adjustments until the specific desired position of the workpiece is attained. During the several reclamping operations, the workpiece may slip or drop out of the clamping device unless it is supported. Used in this manner, the element 22 provides a yieldable support which permits the workpiece position to be adjusted by light hammer taps or the like as the clamp is released without the danger of causing the workpiece to drop down in the vise 16.

In FIG. 6, I have the element 22 used as a hold-down device in clamping the workpiece 26. The ground edge 23 of the element 22 bites into the workpiece to prevent it from being displaced during any of the operations to which it is subjected.

In FIG. 7, I have shown the element 22 used as a kind of resilient V-block for holding a round bar or other circular workpiece 27 in vertical alignment in the clamping device 19. The workpiece 27 is supported in one of the convolutions of the element 22. The walls 28 of the convolution or V are normal to the parallel surfaces 23 of the element 22 and thus align the circular workpiece vertically as well as yieldably clamping it through the action of the jaws 20 and 21. If dmired, two elements 22 could be used on opposite sides of the workpiece 27, instead of only one, as shown.

In FIGS. 17, I have an element 22 in which the configuration of the element is comprised of a series of VS in which the walls 28 of each V are substantially plane and intersect at a crest 29. in FIGS. 8 and 9, I have shown other configurations which might be employed. FIG. 8 shows an element 22a which utilizes angularly disposed walls 28:: similar to the walls 28 but these walls are not brought to a common intersection point. Instead, a plane wall 38, parallel to the longitudinal axis of the element 22a, joins the converging walls 28a and provides a flat crest. In FIG. 9, I have shown an element 22b in which the walls 28b of the element are arcuate and provide a serpentine configuration with softly rounded crests 31 as distinguished from the sharper or more angular crest 29 of the element 22.

FIGS. and 11 show still other modifications which can be made in the form and configuration of the parallel elements herein disclosed. FIG. 10 shows a parallel element 220 which has a V configuration like element 22, but which is rebent as at 32 to provide an integrated pair of spaced elements 22. Similarly, FIG. 11 shows a parallel element 22d which has a serpentine configuration like element 22b but which is rebent as at 33 to provide an integrated pair of spaced elements 2212. In contrast to the element 220 in which the spaced portions 2 2 are in parallelism, FIG. 11 shows the opposite portions 22b of the element 22d to be disposed in symmetry. It will be understood that the form of FIG. 10 could likewise be disposed in symmetry or the form of FIG. 11 could be disposed in parallelism.

The various forms and configurations are shown only by way of example. Combinations of these configurations could be provided or other desired wavelike configurations and variations thereof could be made as requisite or desirable for particular conditions or circumstances. By the term wavelike I intend to define configurations in which the body of the parallel element is formed in a pattern of changing directions to provide laterally extending support surfaces relatively to the median or nominal longitudinal axis of the element.

Although, I find great advantage in utilizing a resilient form of parallel element, as herein disclosed, and consider this to be the preferred and desirable form of my invention, nevertheless, even if the parallel element is not of a resilient character, its forms as herein described provide distinct advantages in weight-saving, space-saving, utility and economy of manufacture which constitute improvements over conventional parallel blocks. Therefore my invention contemplates such devices which are preferably of a resilient character, but not necessarily so.

Although I have described in the utilization of the parallel elements in connection with machining operations (e.g. milling, shaping, drilling, planing, etc.), it will be understood that in machine shop practice the parallel elements could also be utilized during layout or inspection procedures on workpieces, either for production or for tool room work.

It is to be understood that the forms of my invention, herewith shown and described, are to be taken as preferred examples of the same, and that various changes in the shape, size and arrangement of parts may be resorted to, without departing from the spirit of my invention, or the scope of the subjoined claims.

Having thus described my invention, I claim:

1. A parallel workpiece support element of the character described, comprising a body of predetermined height defined by oppositely disposed precision-formed gauging surfaces extending in parallel planes, said surfaces being adapted to engage a workpiece surface and a reference surface respectively, said body being rigid in a direction normal to the planes of said gauging surfaces, and said body being corrugated in said direction of rigidity to provide a wave-like configuration of said gauging surfaces.

2. A parallel workpiece support element of the charac ter described, comprising a body of predetermined height, having a thickness in the range of sheet metal gauges, said height being defined between opposite precisionformed gauging surfaces of said body extending in paral lel planes and adapted to engage a workpiece surface and a reference surface respec "vely, said body being rigid in a direction normal to the planes of said gauging surfaces, and said .gauging surfaces extending in a wavelike configuration.

3. A parallel workpiece support element as defined in claim 2, wherein said body is made of resilient material.

4. A parallel workpiece support element as defined in claim 2 wherein said wave-like configuration comprises a pattern of adjacent V-shaped portions.

5. A parallel workpiece support element as defined in claim 2 wherein said wave-like configuration comprises a serpentine pattern.

6. A parallel workpiece support element as defined in claim 3, wherein said body is rebent upon itself to pr0- vide spaced integrated support portions.

7. A parallel workpiece support element as defined in claim 6, wherein said spaced support portions have parallel configuration patterns.

8. A parallel support element as defined in claim 2, wherein said body is made of a material whereby said wave-like configuration can be compressed to an effective support width substantially approaching the thickness of said body without any permanent deformation set.

References Cited in the file of this patent UNITED STATES PATENTS Re. 21,263 Kaden Nov. 14, 1939 1,895,281 Currie Jan. 24, 1933 2,393,349 Weingarten Jan. 22, 1946 2,484,339 Fuhr Oct. 11, 1949 2,686,957 Koerper Aug. 24, 1954 2,823,460 Weiler Feb. 18, 1958 OTHER REFERENCES Get Increased Production With Improved Machinery, Oct. 7, 1920, p. 697. 

1. A PARALLEL WORKPIECE SUPPORT ELEMENT OF THE CHARACTER DESCRIBED, COMPRISING A BODY OF PREDETERMINED HEIGHT DEFINED BY OPPOSITELY DISPOSED PRECISION-FORMED GAUGING SURFACES EXTENDING IN PARALLEL PLANES, SAID SURFACES BEING ADAPTED TO ENGAGE A WORKPIECE SURFACE AND A REFERENCE SURFACE RESPECTIVELY, SAID BODY BEING RIGID IN A DIRECTION NORMAL TO THE PLANES OF SAID GAUGING SURFACES, AND SAID BODY BEING CORRUGATED IN SAID DIRECTION OF RIGIDITY TO PROVIDE A WAVE-LIKE CONFIGURATION OF SAID GAUGING SURFACES. 